Valve for automatic fire-extinguishers.



No. 770,754. I PATENTED SEPT. 27, 1904.

' J. HUNT.

VALVE FOR AUTOMATIC FIRE EXTINGUISHERSQ APPLICATION FILED JAN. 11, N04.

N0 MODEL.

UNITED STATES Patented September 27, 1904.

PATENT OFFICE.

JARVIS HUNT, OF CHICAGO, ILLINOIS, ASSIGNOR TO PHOENIX FIRE EXTINGUISHERCO., OF CHICAGO, ILLINOIS, A CORPORATION OF NEW JERSEY.

VALVE FOR AUTOMATIC FIRE-EXTINGUISHERS- SPECIFICATION forming part ofLetters Patent No. 770,754, dated. September 27, 1904.

Application filed January 11, 1904. Serial No. 188,498. (No model.)

To all whmn it may concern.-

Be it known that I, JARVIS HUNT, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented certain new and useful Improvements in Valves for AutomaticFire-Extinguishers, of which the following is a specification.

The present invention relates to what is known in the art as the mainvalve, being the valve which is interposed between the street-main orother source of water-supply and the riser of the distributing system.

It is well known to those skilled in the art that in dry-pipe systemsthe main valve, responding to water-hammer and other variations fromnormal conditions, sometimes becomes unseated, possibly onlymomentarily, but when unseated water passes it and fills the system to agreater or less extent. In this way the valve may become columned thatis to say, a column of water accumulates above it-and in some instancesthe column has sufficient Weight or hydrostatic pressure to prevent theopening of the valve even upon the release of the air pressure withinthe system.

There are causes other than water-hammer that result in the columningofthe valve-for instance, when it is fully unseated upon the firing ofone or more heads. In the absence of a catch or some mechanicalappliance for holding it unseated its weight, if greater than the weightof the water which it displaces, may cause it to reseat itself, and ifthis takes place the differential of its upper and lower areas willcause it to be held seated as against the upward pressure of the wateragainst its under side.

The object of the present invention is to provide a valve that cannotunder any circumstances become columned; and to this end the inventionconsists in the features of novelty that are hereinafter described withref erence to the accompanying drawing, which is made a part of thisspecification, and which is a sectional elevation of a valve embodyingthe invention.

The casing A may be of any desired construction. It has a chamber A, aninletorifice B, through which said chamber communicates at bottom withthe street-main or other source of water-supply, and an outletorificethrough which said chamber communicates with the riser of the system,whereby system-pressure is maintained within it. The inlet-orifice iscontrolled by a valve D, which is located in the chamber A, so that itsupper side is exposed to the pressure in the sys tem and its lower sideis exposed to the pressure of the water in the supply-pipe. It may beguided in its movement by a stem E, passing through spiders F and F,located above and below it, respectively. The valve is a float-valve. Inother words, it is buoyant. It is preferably made of metal, its lowerside or bottom, which is provided with annular surfaces d and d, adaptedto contact with the corresponding annular seats a and a, beingsufficiently rigid to answer the purpose of a valve or cut-off, whileits upper portion may be made of thin metal and of only suflicientstrength to resist the pressure within the system. Between theconcentric seats a and a the casing is provided with an annular grooveA, which is known in the art as the lowpressure chamber, being incommunication with the atmosphere through a drain-pipe a". It will bereadily recognized by those skilled in the art that this is a familiarform of differential valve,excepting that, unlike other differentialvalves preceding it in this art, it is sufficiently buoyant to float, sothat without the aid of any catches or other mechanical devices it willremain unseated so long as water stands in its containing-chamber at asufficient depth. It is this that distinguishes it from differentialvalves, such as heretofore constructed and which makes it absolutelyimpossible for it to become columned. It is manifest that so long as thesystem remains in normal condition and charged with air under pressurethe differential areas of the valve will enable the comparatively lightair-pressure above it to hold it closed as against the heavywater-pressure below it. In the event of a momentary unseating of thevalve due to water-hammer the small quantity of water passing the seat awill be received in the groove or low-pressure chamber A and will escapethrough the drain-pipe a. If, on 'the other hand, the quantity of waterpassing the valve is too great to be led off in this way and forms acolumn above the valve, the buoyancy of the valve will unseat it and thetheretofore dry-pipe system is simply converted into a wet-pipe system.This may be made manifest by the use of any suitable alarm mechanism. Inthe drawing I have diagrammatically represented an electrical alarmconsisting of a battery, an alarm-bell, and an open circuit havingcontacts that will be closed by the stem E of the valve when it rises. Idesire to have it understood, however, that the invention is in no waylimited to the construction or character of the alarm device.

I am aware that it has heretofore been proposed to use afloat forunseating a valve which controls a passage from the low pressure chamberto the airchamber or system and which float unseats said valve and openssaid passage whenever the water rises up in the system to a given level.I am not aware, however, that it has ever been proposed to use in a fireextinguishing system a main valve of such buoyancy that it will beunseated by the combined influences of its own buoyancy and the pressurein the service-pipes whenever the water rises up in the system to agiven level and that by reason of its buoyancy alone it will remainunseated so longas its containing-chamber contains a suflicient quantityofwater.

What I claim as new, and desire to secure by Letters Patent, is-

1. In a valve for automatic fire-extinguishers the combination of acasing having a chamber under system-pressure, an inlet through whichsaid chamber communicates with a water-supply, and a differential valvelocated in said chamber and having its opposite sides exposed to thesystem-pressurev and waterpressure, respectively, said valve beingsufficiently buoyant to remain unseated so long as itscontaining-chamber contains a suflicient quantity of water,substantially as described.

2. In a valve for automatic fire-extinguishers, the combination of acasing having a chamber under system-pressure, an inlet through which itcommunicates with a water-supply, difierential valve-seats surroundingthe inlet, and a low-pressure chamber between the valveseats, a valvelocated in the chamber first aforesaid and having working faces adaptedto said valve-seats, said valve having its opposite sides exposed to thesystem-pressure and water-pressure, respectively, and being buoyant andadapted to be held unseated by its own buoyancy, substantially asdescribed.

3. In a valve for automatic fire-extinguishers, the combination of acasing having a chamber under system-pressure, an inlet through saidvalve being hollow and sufliciently bouyant to remain unseated in thepresence'of water, substantially as described.

4. In avalve for automatic fire-extinguishers, the combination with acasing having a chamber and having at bottom an inlet through which saidchamber communicates with a source of water-supply and having also anoutlet through which said chamber communicates with the system, of abuoyant difl'erential valve located in said chamber for controlling theinlet, the under side-of said valve being exposed to the comparativelyhigh water-pressure and the upper side of said valve being exposed tothe comparatively low air-pressure, substantially as described.

5. In a valve for automatic fire-extinguishers, the combination with acasing having a chamber and having at bottom an inlet through which saidchamber communicates with a with the system, and having alsodifferential Valve-seats surrounding the inlet, and a lowpressurechamber between the valve-seats, of a buoyant difl'erential Valvelocated in said chamber and having working faces adapted tosaid'valve-seats, the under side of the valve being exposed to thecomparatively high pressure of the water and the upper side of the valvebeing exposed to the comparatively low pressure of the air in thesystem, substantially as described. 6. In a valve for automaticfire-extinguishers, the combination with a casing having a chamber andhaving at bottom an inlet through which said chamber communicates with asource of water-supply and having also an outlet through which saidchamber communicates with the system, and having also a low-pressurechamber disposed between the inlet and the outlet, of a valve located insaid chamber and having differential seating-surface for-controllingcommunication between the inlet and the low-pressure chamber and betweenthe low-pressure chamber and the chamber first aforesaid, said valvebeing hollow and sufliciently buoyant to remain unseated when submerged,the under side of said valve being exposed to the comparatively highwater-pressure and the upper side being exposed to the comparatively lowair-pressure, substantially as described.

JARVIS HUNT. Witnesses:

W. E. KLEINPELL, L. M. HOPKINS.

